The Transportation Security Administration has been working on its image, engaging readers on its blog with the latest travel security information, inviting fans to “meet the bloggers” and more. The TSA is also finding that its message is more palatable with a dose of humor.

This week on its Transportation Tips post, TSA asks readers to please leave their grenades at home. “After reading the title of this post, your first thought probably was, ‘That’s obvious.’ Not always so”, writes Bob Burns. Just this year, TSA officers have discovered 43 grenades in carry-ons and 40 in checked luggage.

Most of the grenades were inert, replica or novelty items, like antiques someone might buy on eBay. “But a few were live smoke, flare, riot, and flash bang grenades, which can pose major safety issues to aircraft and also violate FAA hazmat regulations,” added Burns.That the majority of grenades TSA sees won’t actually explode isn’t the issue. The problem is that they look just like real grenades during screening, slowing down the process, if not closing and evacuating terminals.